The determination of an acoustic impulse response is a task that is associated with various applications. These include, on the one hand, non-room acoustic investigations of a test system, for example, the characterising of loudspeakers or other acoustic signal sources and, on the other hand, the room acoustic investigation of a test system, in particular the analysis of the acoustics of rooms wherein a room acoustic impulse response or acoustic room impulse response is determined.
Usually, when an acoustic impulse response is determined, an input signal is provided and emitted by an acoustic signal source. In the case of loudspeaker analysis, the input signal is emitted by the loudspeaker. The acoustic signal fed in ‘convolves’ with the impulse response of the system to be analysed. An acoustic output signal is produced. When rooms are investigated, the acoustic signal can be measured with an acoustic measuring device, for example, a microphone.
The signals that can be evaluated are therefore the acoustic input signal and the acoustic output signal or acoustic signals derived therefrom following optional processing. Using a known mathematical tool, the acoustic signals can be subjected to a Fourier transformation in the frequency domain, which produces: A(ω)=E(ω)×H(ω), where A(ω) is the Fourier transform of the measured acoustic output signal, E(ω) is the Fourier transform of the acoustic input signal and H(ω) is the Fourier transform of the as yet unknown impulse response. Rearranging gives: H(ω)=A(ω)×E(ω)−1. From this, using inverse Fourier transformation, the acoustic impulse response h(t) in the time domain can easily be determined.
FIG. 1 shows a schematic representation in order to illustrate a known measuring arrangement for determining an acoustic impulse response. With the aid of a control device 1 comprising a signal generator 1a and an evaluating device 1b, acoustic signals are generated wherein said signals are, for example, noise signals, sweeps (sliding sinusoidal signals), speech signals or music signals passed via a digital-analogue converter 2 (DAC) to an acoustic signal source 3 via which an acoustic input signal 4 is emitted. With the aid of an acoustic measuring device 5 configured as a microphone, an acoustic output signal is detected and transmitted via an analogue-digital converter 6 (ADC) to the evaluating device 1b, which in the illustration of FIG. 1 is integrated with the signal generator 1a. 
It is common to the known methods for determining an acoustic impulse response that, in a measuring step, the acoustic output signal is first detected. In a subsequent process, for example in a laboratory, the acoustic impulse response is then calculated, whether in the context of a room acoustic or a non-room acoustic investigation. This process is also known as a static method for determining the impulse response. Furthermore, for non-room acoustic investigations, that is for example, in conjunction with the characterising of loudspeakers, a real-time measurement of brief non-room acoustic impulse responses impulse responses and frequency responses is also known. However, these are only non-room acoustic impulse responses which are limited temporally to a length of no more than one or two seconds.